<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>3D旋转</title>
    <style>

        body{
            perspective: 500px;
        }

        .b1{
            margin: 100px auto;
            width: 320px;
            height: 320px;
            background: url("../../Img/pig.jpg");
            transition: all 1s;
        }

        .b1:hover{
            transform: rotateZ(-180deg);
        }

    </style>
</head>
<body>
<div class="b1">

</div>
</body>
</html>